deal with race condition in testing for channel closure

The client may receive & process the channel.close before txCommit is
invoked, in which case an AlreadyClosedException is thrown rather than
the expected IOException (which is what you get when the channel.close is
handled later).

Author: Matthias Radestock

test/src/com/rabbitmq/client/test/functional/TransactionsBase.java

@@ -33,6 +33,7 @@
 
 import java.io.IOException;
 
+import com.rabbitmq.client.AlreadyClosedException;
 import com.rabbitmq.client.GetResponse;
 import com.rabbitmq.client.AMQP.BasicProperties;
 
@@ -256,7 +257,9 @@ public void testUnknownTagAck()
         try {
             txCommit();
             fail("expected exception");
-        } catch (IOException e) {}
+        }
+        catch (IOException e) {}
+        catch (AlreadyClosedException e) {}
         connection = null;
         openConnection();
     }